Method for loading automatically machines for treating bulk materials and device for working such method

Abstract

There is described a method and apparatus for loading automatically, machines treating bulk materials in which from the bottom of a material mass is extracted, with projecting elements, an amount of material to form a strip. The strip is fed to the treating machines. The apparatus comprises arranging the projecting elements into at least two rows extending along the strip movement direction, and imparting to at least one element row, an alternating movement along the strip movement direction.

1.  An apparatus for automatically loading a machine which treats bulk materials, said bulk materials having some length and including materials such as fibers, yarns, fragments from woven or unwoven textiles, and plastics, said apparatus extracting from the bottom of a material mass, by means of projecting elements entering said mass, an amount of material to be formed into a strip which is to be fed to said machine, said apparatus comprising: a hopper having a top and a bottom and four sides and being mounted on a fixed frame, the hopper top and bottom being open and along the hopper edge nearest to the machine to be loaded is provided a quadrangular opening extending from the hopper bottom, the cross-section of said opening substantially corresponding to the cross-section of said strip to be formed, the hopper bottom being shaped as a quadrilateral with four right angles and said opening being provided along one quadrilaterial side;   at least two rows of projecting elements arranged in the hopper bottom, substantially at right angle to the hopper edge along which said opening is provided and at a lower level than the edge of said opening opposite the hopper bottom;   two movable bars on which are fixed the at least two rows of projecting elements, said two movable bars closing--off the hopper bottom and extending at right angles to said opening;   guides for causing said two movable bars to move along their lengthwise axis, the length of said bars being longer than the length of the hopper bottom, so that said two movable bars always close-off the hopper bottom;   control means provided to drive each one of said two movable bars with an alternating motion such that the projecting elements from each row move from the hopper side opposite said opening to beyond said opening, said control means being arranged so that during the time interval where one bar moves from said opening to said hopper side opposite said opening, the other bar moves in the opposite direction or is stopped; and   means to feed said material to said hopper.   
     
     
       2. An apparatus as claimed in claim 1, in which said projecting elements are arranged in parallel relationship with a vertical plane which passes through the lengthwise axis of the material strip to be formed. 
     
     
       3. An apparatus as claimed in claim 1, which further comprises a knife arranged inside the hopper and mounted thereon adjacent said opening, substantially in parallel relationship with the hopper bottom, and at a distance from said bottom which is slightly shorter than the spacing between the opening edge opposite said bottom and at a higher level than the projecting elements so that the projecting elements pass below said knife as they drive the material beyond the opening. 
     
     
       4. An apparatus as claimed in claim 1, which further comprises, in a zone lying between ends of the at least two rows of projecting elements, at least one cutting element lying between at least two rows of projecting elements. 
     
     
       5. An apparatus as claimed in claim 1, in which the hopper sides extending along the quadrilateral sides adjacent to the one quadrilateral side where said opening is provided, each have a vertical zone extending from the hopper bottom to a height which is at least equal to the height of said opening, each of said vertical zones being extended with a slanting zone to form a hopper flare, the size of the opening, which is at right angles to said bar movement direction, being substantially equal to the spacing between said vertical zones. 
     
     
       6. An apparatus as claimed in claim 5, in which said vertical zones are in the shape of a triangle the apex of which lies on the hopper bottom and on the quadrilateral side opposite the one quadrilateral side provided with said opening, and the base of which merges with the one quadrilateral side provided with said opening. 
     
     
       7. An apparatus as claimed in claim 5, in which the hopper comprises along the edge of said opening opposite the hopper bottom, a guide sheet for the upper surface of the material strip, said guide sheet extending inside the hopper and joining said vertical zones, the knife being arranged adjacent a guide sheet edge which lies opposite said opening, the spacing between said guide sheet edge opposite said opening and the hopper bottom being slightly smaller than the spacing between a guide sheet edge adjacent the opening and said hopper bottom. 
     
     
       8. An apparatus as claimed in claim 7, in which the hopper side lying above said opening is convex and extends from the knife above said guide sheet in such a way as to return the material being cut away from said strip to the material mass bearing on said bars. 
     
     
       9. An apparatus as claimed in claim 1, in which the hopper side opposite said opening is provided with a cut-out to let the projecting elements pass beyond said hopper side opposite said opening as said projecting elements move in the opposite direction to the strip, the size of said cut-out corresponding substantially to the size of said opening. 
     
     
       10. An apparatus as claimed in claim 9, in which the hopper further comprises a movable hood hinged outside the hopper to close-off said cut-out, said hood being arranged so as to cover said projecting elements as they move beyond the hopper side which is provided with the cut-out, the hood hinge being arranged so as to allow movement of said hood for uncovering said cut-out. 
     
     
       11. An apparatus as claimed in claim 1, which further comprises means arranged so as to insure that the material falls down to the hopper bottom. 
     
     
       12. An apparatus as claimed in claim 11, wherein said means is comprised of additional projecting elements which are arranged on the bars nearest the hopper sides which are in parallel relationship with said bars, said additional projecting elements having a height which is higher than said projecting elements and said additional projecting elements being mounted on the bars so that their movement is limited to not reach the knife; and wherein said hopper side opposite said opening has a cut-out with a height which allows said additional projecting elements to pass therethrough.   
     
     
       13. An apparatus as claimed in claim 12, in which said additional projecting elements are of triangular shape and are secured to the bars with their base along a vertical plane passing through the bar lengthwise axis, the additional projecting elements being shaped so that the projection on the bar of said triangle apex falls outside the triangle base towards said opening. 
     
     
       14. An apparatus as claimed in claim 11, in which said means provided to insure that the material falls to the hopper bottom is comprised of movable members supported by the hopper sides and controlled so as to move between two end positions, one end position being where said movable members engage the hopper sides, and the other end position being where said movable members are moved away from the hopper sides to cause said material mass to fall on the projecting elements. 
     
     
       15. An apparatus as claimed in claim 1, in which said hopper is hinged to the frame about an axis at right angles to the vertical plane passing through the lengthwise axis of one of said bars, said axis lying directly adjacent to the hopper side opposite to said opening, in such a way that swinging of the hopper about said axis allows adjusting the height of said opening, the frame comprising means for locking the hopper in the selected position thereof. 
     
     
       16. An apparatus as claimed in claim 1, in which said means for feeding material to the hopper is comprised of a bucket hinged to said frame, and means for controlling said bucket arranged on said frame to let said bucket take two end positions, a first end position being where the bucket lies substantially horizontally at such a distance from the ground that the material to be fed to the hopper can be discharged into the hopper, and a second position in which said bucket is tipped over the hopper to let the material fall by gravity.